The effect of ionic liquid containing AlCl3 catalytic systems on the microstructure and properties of polyalphaolefin based lubricants

A new class of ionic liquid (IL) containing AlCl3 catalysts was synthesized from 1-methylimidazole, and different alkyl chlorides, including: 1-butyl chloride, cyclohexyl chloride and benzyl chloride, named as IL-But/AlCl3, IL-CH/AlCl3 and IL-Benz/AlCl3, respectively. The as-synthesized catalysts were employed along with half dosage of AlCl3 in the 1-decene oligomerization to related polyalphaolefins (PAOs), as a less-toxic alternative to the conventional, corrosive and toxic AlCl3 and BF3 catalysts. Besides aiming to achieve new, safer and cost-effective catalyst, the microstructure-flow properties of the synthesized oils were studied by using various techniques. Results revealed that the catalytic efficiency of IL/AlCl3 catalysts can be tuned by the proper choice of alkyl chloride. IL-Benz/AlCl3 and IL-CH/AlCl3 yielded more uniformly structured PAOs with low molecular weight, kinematic viscosity (KV), and short chain branching, but, higher viscosity index (VI) values. However, IL-CH/AlCl3 resulted PAO whose characteristic was very close to the one obtained by neat AlCl3. Synthesized from greener IL/AlCl3 system, in which the loading of AlCl3 as catalyst is halved, together with enabling to control PAO microstructure by proper selection of IL ligand are substantial achievements of the suggested catalytic systems. (C) 2021 Elsevier B.V. All rights reserved.

Automated summary

A new class of ionic liquid containing AlCl3 catalysts was synthesized and used in 1-decene oligomerization to produce PAOs, offering a less-toxic alternative to traditional AlCl3 and BF3 catalysts. Different alkyl chlorides were employed to tune the catalytic efficiency, resulting in PAOs with varying microstructure and flow properties. The use of IL/AlCl3 system with reduced AlCl3 loading and proper selection of IL ligand allowed for control of PAO microstructure, showcasing significant achievements in the suggested catalytic systems.